Ask most people what a $100,000 buy order does and they will say "the price goes up." True, but useless. How far up depends entirely on what was standing in the way — and that is a number you can look at before the order lands.
An order does not get one price
A market order is not filled at the price you saw. It is filled at every price it has to climb through until it is done. Say the asks look like this:
| Price | Size available | Value |
|---|---|---|
| $1.0000 | 18,000 | $18,000 |
| $1.0005 | 25,000 | $25,010 |
| $1.0010 | 12,000 | $12,012 |
| $1.0025 | 60,000 | $60,150 |
A $100,000 market buy clears the first three levels entirely and takes about $45,000 out of the fourth. The average fill lands near $1.0014, and the new price on everyone's screen is $1.0025 — a 0.25% move from one order. The buyer paid roughly $140 more than the screen price suggested. That gap is slippage, and it is the real cost of impatience.
The same order in a deep book
Run the identical $100,000 into BTC-USD, where each price level holds far more, and it disappears without a trace — often filling inside a single level. Same money, same intent, no visible impact.
This is why "whale bought $100k" means nothing without the second half of the sentence. A hundred thousand dollars is a rounding error in Bitcoin and a genuine event in a thin altcoin market. Depth, not size, decides impact.
Walls: the fortification that hides the truth
Sometimes one participant parks an enormous resting order at a single price. Buyers charge into it and get filled at exactly that price, again and again. Price flatlines.
Two things are worth knowing about walls. First, they are the most reliable thing to fade right up until they are not: while it holds, the wall is free absorption. Second, a wall that breaks releases everything at once — the pressure that was being eaten now hits levels with nothing behind them, so the move on the far side is faster than the move into it.
And walls lie. A resting order can be cancelled in a millisecond. Some are placed with no intention of ever being filled, purely to shape what other people believe — spoofing. It is illegal in regulated markets and endemic in unregulated ones. The tell is simple: real walls get eaten, fake walls vanish the instant price approaches.
Why big traders slice
Anyone moving serious size knows all of the above, which is why they almost never send it in one order. They slice it — a few thousand dollars at a time, spread over minutes or hours, sometimes matched to a share of overall volume.
Sliced flow is visible if you know what you are looking at: repeated similar-sized trades, same side, evenly spaced, unbothered by small price moves. A human does not trade like a metronome. When you see the metronome, an institution is in the market and it is not finished.
What this means for you
- Check depth before size. "Is $50,000 big here?" is answered by the book, not by the number.
- Expect slippage on thin books. If the market moves 0.25% on a $100k order, your own market order pays that same tax on the way in and again on the way out.
- Watch what a wall does, not that it exists. Eaten steadily is real supply. Disappearing on approach was never there.
- One print is not a signal. A single large trade is somebody's decision, not the market's. The pattern of prints is the signal.
All of this is legible in real time and free to watch. In our board, size becomes rank: trades under $10,000 arrive as infantry, $10,000 and up as armour, and anything over $100,000 calls in air support — so a whale is not a row in a log you missed, it is a jet crossing the field while the line moves under it.